[skip sauce]
[skip validator]

"bootstrap@4.0.0-alpha license should be a valid SPDX license expression"

Closes #16636 by merging a rebased+tweaked version of it.
[skip sauce]

Specifying both the type and URL is deprecated:
* https://docs.npmjs.com/files/package.json#license
* http://npm1k.org/

Closes #16517

Add a license header in theme instead.

Bump mq4-hover-shim to ^0.2.0

Revert "fix dist css"
This reverts commit b12d4bfa.

[ci skip]

[skip sauce]
[skip validator]

Only used for the GitHub docs.

[skip sauce]
[skip validator]